Greensborough Highway Patrol officers are appealing for public assistance as they investigate a five-car collision in Thomastown yesterday morning.
It is understood a brown Toyota utility was travelling east on the Metropolitan Ring Road between the Edgars Road on ramp and the Dalton Road on ramp when it collided with a white Toyota sedan about 5.30am on Thursday, 28 November.
Officers have been told the Toyota utility failed to stop after the initial collision, continuing to drive erratically east bound on the Ring Road, before crashing into two concrete barriers nearby.
As the brown Toyota utility came to a stop, it is believed an oncoming grey Toyota utility collided with the vehicle.
A fourth vehicle, a white Isuzu utility, managed to avoid colliding with the two Toyota utilities.
However, a fifth vehicle, a blue Mazda sedan, was unable to stop and collided with the white Isuzu utility.
The multiple collisions caused the east bound lanes of the Ring Road to close for approximately two hours.
The driver of the brown Toyota utility, a 19-year-old Glenroy man, was taken to hospital under police guard.
He has since been released pending further enquiries.
The driver of the grey Toyota utility, a 55-year-old Broadford man, was taken to hospital with serious injuries.
The drivers of the blue Mazda sedan, the white Isuzu utility, and the white Toyota sedan were not injured.
Police continue to investigate the circumstances surrounding the collisions.
Anyone who witnessed the incident, with dashcam/CCTV vision or information is urged to contact Crime Stoppers on 1800 333 000 or submit a confidential report online at www.crimestoppersvic.com.au